1. Field of the Invention
The invention relates to a stopping position control apparatus and stopping position control method of an internal combustion engine. More particularly, the invention relates to a stopping position control apparatus of an internal combustion engine to which control for automatically stopping and restarting the internal combustion engine when a vehicle temporarily stops can be applied, as well as a control method thereof.
2. Description of the Related Art
Japanese Patent Application Publication No. JP-A-2004-293444, for example, describes a starting apparatus of an engine which executes control (eco-run control) for automatically stopping and restarting an internal combustion engine when a vehicle temporarily stops. This related technology aims to optimize the piston stopping position (i.e., the crankshaft stopping position) when automatically stopping the engine, by controlling the engine speed at the time the fuel supply is stopped so that the internal combustion engine will restart smoothly the next time.
The effect of friction on the crankshaft may cause the crankshaft stopping position to be off from the target stopping position when automatically stopping the internal combustion engine. The effect of this friction can change depending on whether a clutch arranged between the internal combustion engine and a transmission is engaged when the internal combustion engine is automatically stopped. The related method does not take this into consideration so there remains room for improvement in order to realize an apparatus that accurately estimates the crankshaft stopping position taking the foregoing friction into account.